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8
Panels B and C (YFZ450RB)
To remove a panel
1. Remove panel A.
2. Pull the panel off.
To install a panel1. Place the panel in the original position. 2. Install panel A.
Cowling (YFZ450RB)
To remove the cowling
1. Remove panels A, B and C.
2. Remove the bolts, and then take the cowling off.
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8-12
8To install the cowling
1. Place the cowling in the original position, and
then install the bolts.
2. Install panels C, B and A.EBU29595Panel A (YFZ450RSEB)
To remove the panel1. Remove the seat. (See page 4-10.)
2. Remove the fuel tank cap by turning it coun- terclockwise. (See page 4-8.) NOTICE: Make
sure that no foreign material enters the
fuel tank.
[ECB01051]
3. Loosen the quick fasteners.
1. Bolt
1. Bolt
11
1
1
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8
4. Remove the quick fasteners, and then slide
the panel backward and pull upward. 5. Install the fuel tank cap by turning it clockwise.
To install the panel
1. Remove the fuel tank cap by turning it coun- terclockwise.
2. Place the panel in the original position, and then install the quick fasteners. NOTICE:
When installing the panel, be sure not to
pinch the cables or wires.
[ECB00381]
3. Tighten the quick fasteners.
4. Install the fuel tank cap by turning it clockwise.
5. Install the seat.
1. Quick fastener
1. Quick fastener
1 1
1
1. Projection
2. Slot
11
2
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8-14
8Panels B and C (YFZ450RSEB)
To remove a panel
1. Remove panel A.
2. Pull the panel off.
To install a panel1. Place the panel in the original position. 2. Install panel A.
Cowling (YFZ450RSEB)
To remove the cowling
1. Remove panels A, B and C.
2. Loosen the quick fasteners, and then take the cowling off.
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8-15
8
To install the cowling
1. Place the cowling in the original position, and
then tighten the quick fasteners.
2. Install panels C, B and A.EBU29441Checking the spark plug The spark plug is an important engine component,
which should be checked periodically, preferably
by a Yamaha dealer. Since heat and deposits will
cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
The porcelain insulator around the center elec-
trode of the spark plug should be a medium-to-light
tan (the ideal color when the vehicle is ridden nor-
mally). If the spark plug shows a distinctly different
color, the engine could be operating improperly.
Do not attempt to diagnose such problems your-
self. Instead, have a Yamaha dealer check the ve-
hicle.
If the spark plug shows signs of electrode erosion
and excessive carbon or other deposits, it should
be replaced.
1. Quick fastener
1. Quick fastener
11
1
1
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8-16
8Before installing the spark plug, the spark plug gap
should be measured with a wire thickness gauge
and, if necessary, adjusted to specification.
Clean the surface of the spark plug gasket and its
mating surface, and then wipe off any grime from
the spark plug threads.
TIPIf a torque wrench is not available when installing
the spark plug, a good estimate of the correct
torque is 1/4
–1/2 turn past finger tight. However,
the spark plug should be tightened to the specified
torque as soon as possible.EBU29499Engine oil and oil filter element The engine oil level should be checked before
each ride. In addition, the oil must be changed and
the oil filter element replaced at the intervals spec-
ified in the periodic maintenance and lubrication
chart.
To check the engine oil level 1. Place the ATV on a level surface.
2. Start the engine, warm it up until the engine oil has reached a normal temperature of 40 °C
(104 °F), let it continue to idle for ten seconds
or more, and then turn the engine off.
Specified spark plug:
NGK/CR8E
1. Spark plug gapSpark plug gap:0.7– 0.8 mm (0.028 –0.031 in)
Tightening torque:
Spark plug:13 Nm (1.3 m ·kgf, 9.4 ft ·lbf)
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8
TIPTo achieve the proper engine oil temperature for
an accurate oil level reading, the engine must have
first completely cooled down, and then warmed up
again for several minutes to normal operating tem-
perature.3. Remove the engine oil tank filler cap, andwipe the engine oil dipstick off with a clean
rag.
4. Insert the dipstick into the filler hole (without screwing it in), and then remove it again to
check the oil level.TIPThe engine oil should be between the minimum
and maximum level marks.
5. If the engine oil is at or below the minimumlevel mark, add sufficient oil of the recom-
mended type through the engine oil tank filler
hole to raise it to the correct level. NOTICE:
Be sure the engine oil is at the correct lev-
el, otherwise engine damage may result.
[ECB00851]
1. Engine oil tank filler cap
2. Engine oil dipstick
3. Maximum level mark
4. Half-level mark
5. Minimum level mark1 1
2
3
54
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8
TIPWhen adding oil, be careful not to overfill the en-
gine oil tank; the oil level rises faster starting from
the half-level mark on the dipstick.6. Insert the dipstick into the engine oil tank fillerhole, and then tighten the engine oil tank filler
cap. NOTICE: Make sure that the engine oil
tank filler cap is securely tightened; other-
wise, oil may seep out when the engine is
running.
[ECB00362]
To change the engine oil (with or without oil fil-
ter element replacement) 1. Place the ATV on a level surface.
2. Remove the engine guard by removing the bolts. 3. Start the engine, warm it up for several min-
utes, and then turn it off.
4. Place an oil pan under the engine to collect the used oil.
5. Remove the engine oil tank filler cap, and then remove the engine oil tank drain bolt and its
gasket.
1. Engine guard
2. Bolt
2 21
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